=over

=item getppid
X<getppid> X<parent> X<pid>

Returns the process id of the parent process.

Note for Linux users: Between v5.8.1 and v5.16.0 Perl would work
around non-POSIX thread semantics the minority of Linux systems (and
Debian GNU/kFreeBSD systems) that used LinuxThreads, this emulation
has since been removed.  See the documentation for L<$$|perlvar/$$> for
details.

Portability issues: L<perlport/getppid>.

=back